Revert "Bump maven-release-plugin from 3.0.0-M5 to 3.0.0-M7"

This reverts commit 3804c82.

Reason: apache/maven-release#125 (comment)

Author: famod

pom.xml

@@ -94,7 +94,7 @@
         <version.maven-gpg-plugin>3.0.1</version.maven-gpg-plugin>
         <version.nexus-staging-maven-plugin>1.6.13</version.nexus-staging-maven-plugin>
         <version.versions-maven-plugin>2.13.0</version.versions-maven-plugin>
-        <version.maven-release-plugin>3.0.0-M7</version.maven-release-plugin>
+        <version.maven-release-plugin>3.0.0-M5</version.maven-release-plugin>
         <version.spotbugs-maven-plugin>4.7.2.1</version.spotbugs-maven-plugin>
         <version.spotbugs>4.7.3</version.spotbugs>